What Does an ECG Chart Show?

When you have an ECG at the London clinic, the machine will produce a chart showing the changes in electrical activity in your heart over time. The doctor can use this chart to diagnose a range of different conditions that might be affecting your heart.

How Your Heart Beats

Your heart has four chambers. The two upper chambers or atria contract first, followed by the two larger chambers or ventricles beneath them. The contractions are timed by electrical signals that have to happen in the right way to produce a healthy, regular heartbeat. If something is wrong with the signals, then your heart might not beat in the right way. These kinds of problems can be detected by an ECG test in London.

Your ECG Results

The ECG machine at the London cardiac clinic isn’t able to measure the contractions directly, but it can detect the electrical activity associated with these changes in your heart. The results are shown in the form of a graph that looks like a spiky line.

The spikes should appear in regular clusters, each of represents one whole heartbeat. The distance between these spikes shows your heart rate. If the distances are too short, too long, or irregular, it can be a sign of a problem. For example, spikes that are too close together are a sign of a rapid heartbeat or tachycardia.

Each heartbeat will be made up of several spikes in activity. The first P wave shows when the atria are contracting. The second and biggest spike, known as the QRS complex, occurs when your ventricles contract. The final increase in activity is the T wave, which happens as the ventricles relax again. You can’t see a separate spike when the atria relax because it happens at the same time as the ventricles contract. The spikes in electrical activity should occur in the right order, at the right time. Anything unusual in the pattern of the spikes could be a sign of a heart problem. For example, if there are lots of extra little P waves, it is a sign of atrial fibrillation.